Understanding Estimation Accuracy
How we calculate. Accuracy % = (1 − absolute error ÷ actual) × 100 (can be negative if error > actual). The form uses the same arithmetic as the worked examples on this page. See our methodology and accuracy policy.
Real-world scenario: A typical Estimation Accuracy case uses actual 120 and estimate 100. Enter the same figures below to reproduce the worked path.
What is Estimation Accuracy?
A simple forecasting skill metric for teams. Magnitude of Relative Error (MRE) is |A−E|/A; accuracy here is 1 − MRE as a percent.
- Same units for actual and estimate
- 100% = perfect
- Negative means error exceeded the actual
The Formula
Worked Example
Common Use Cases
- Retro metrics: estimate skill
- Vendor scorecards: bid accuracy
- Coaching: improve planning poker
Pro Tips
- Track by work type
- Prefer rolling averages
- Don’t punish learning estimates unfairly
Limitations: Estimation Accuracy results are educational software estimation aids—not bids, contracts, or performance scores. Calibrate models to your organization’s history.
FAQ
Why not just percent error?
Percent error is related; this framing reports “accuracy” as 100% minus relative absolute error.
What if actual is 0?
Accuracy is undefined—actual must be non-zero.
Authoritative References
For estimation and quality models, consult:
- COCOMO — Constructive Cost Model overview
- IFPUG — function point standards
- SEI / Carnegie Mellon — software engineering practice